Safety-valve



' (No Model.)

0. w. GIBSON.

- SAFETY VALVE.

No. 469,853. Patented Mar. 1, 1892.

' /I J" J J 1' a J l 0 Wain/asses [mam/[0)":

6711011117 Zflabdon 76 M J5 UNITED STATES dHAUNcEY w. GIBSON,

PATENT OFFICE.

OF DETROIT, MICHIGAN.

SAFETY-VALVE.

SPECIFICATION forming part of Letters Patent No. 469,853, dated March 1, 1892.

Application filed November 28, 1891. Serial No. 413,399. (No model.)

T0 or whom it may concern.-

Be it known that I, CHAUNOEY W. GIBSON, a citizen of the United States, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Safety-Valves, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to new and useful improvements in safety-valves; and it consists in the peculiar arrangement and combination of the various parts, all as more fully hereinafter described.

In the drawings, Figure l is a vertical central longitudinal section through myimproved valve. Fig. 2 is a top plan view thereof.

A is a casing of the receptacle to which my safety-valve is to' be applied.

13 is the casing of the valve, preferably of cylindrical form, provided at its lower end with the coupling 0, suitably screw-threaded to engage through the casing of the receptacle. This coupling is provided with a central aperture D, communicating with the interior of the casing B of the valve. Surrounding the upper end of this aperture is a raised seat E, preferably of conical form, against which a valve F is adapted to be seated. This valve I form with a central recess G, adapted to hold a hard-rubber or other suitable disk H, of proper size to rest upon the seat E around the aperture D.

I is the stem of the valve, extending up through the tubular casing B to the top thereof.

J is a spring resting at its lower end upon the valve and at its upper end bearing against the plug K, which is suitably screw-threaded to engage in the screw-threads formed on the inside of the casing B. The upper end L of the valve-stem is of triangular or rectangular shape and engages through a correspondinglyshaped aperture M in the plug K. This plug is provided with suitable notches N, adapted to receive a spanner or wrench forturning the same. Y

O are outlets for the escaping fluid which passes through the channel D in the nipple.

The parts being thus constructed to give the necessary pressure to the valve F, I apply the spanner in the notch N of the plug and rotate that plug, moving it downward within the casing and compressing the spring, to the peculiar angular shape of the upper end of the. stem L and its engagement in the corresponding aperture. It is evident that the valve may be turned with the stem so as to be ground firmly upon the seat to perfectlyfit the same, being held thereon by the springpressure, and in case the valve should leak at any time a turn of this plug Will not only tighten the spring-pressu re, but will also tend to grind the valve to its seat simultaneously. I have found by experiment that ordinarily in such safety-valve the disk is rotated to grind it to its seat, and thus with my construction in applying the pressure to the spring I grind it to its seat and prevent any danger of leakage.

WVhat I claim as my invention is 1. In a safety-valve, the combination of a casing, the valve and its stem, a spring for said valve, and an adjusting-plug for said spring with which the valve-stem engages in a manner to rotate said stem in the rotation of plug, substantially as described.

2. In a safety-valve, the combination of the apertured casing, the valve therein, the stem of said valve extending longitudinally through the casing and having an angularlyshaped upper end, a spring sleeved upon said stem, hearing at its lower end upon the valve, and a screw-plug engaged into the casing and having a correspondingly-shaped aperture to the shape of the stem and adapted to simultaneously rotate said valve upon its seat in the adjusting of said plug, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

J AMES WHITTEMORE, M. B. ODOGHEETY. 

